Pulverized-coal-feeding apparatus.



LA RUE a. C HE VAU-ER. PULVERIZED COAL FEEDING APPARATUS. APPLICATIbN men uAn. 1916.

1,203,703. Patented Nov. 7,1916.

' fzverwo 7 i Mum: a

Kansas, have invented certain new UNITED STATES PATENT 1.5 nun B. cnnvamnn, or, 1014A,- x ansa's.

,PULVEBIZEDrCOAP-FEEDING h-Il Specification or Letters Patent.

" Patented unit-7,1916. 1

Application filed mueh'c, 1916. Serial m. 82,392

whereby the fuel may be delivered from a.

common source vof supply to a number of burners in asingle furnace or ta a number of burners of two or more separate furnaces, dispensing with the use-of a separate coal bin and feeding device for supplying each burnerf secondly, whereby it becomes possible, with the use of powdered coalas fuel,

to maintain furnaces of larger area than heretofore at a substantially even tempera ture throu hout; thirdly, whereby a predetermined pressure of air carrying the proper quantity of powdered coal for fuel may be 'maintalned in a passageway which is connected to and feeds a number of separate burners; .fourthly, whereby the air may: be

caused to circulate throu h' an endless passageway, so t at any coa carried by the circulating air which passes all the burners 'without being fed 'to them may be again returned to the burners; fifthlyfwhereby a y desired number. of the plurality" of b rners connected to the main fuel supply passageway may. be open for operation at any time; sixthly, whereby the'--main fuel supply passageway. may be"supp1ied with powdered the operation of the apparatus; seventlily,

whereby the unused coal passlng the burners may be returned to the supply bin; eighthly, whereby the air pressure in the main fuel supply passageway may be automatically regulated by the pressure itself; ninthly,

whereby the se arator or dust collector usually employe in pulverized coal feeding apparatus, may: be dispensed with; and, finally,

With this object inwiew' my improved apparatus consists ofithe elements and the combinations of them hereinafter fully described and claimed. Y a In -the accompanying drawings illustrat- -is an elevation thereof. Fig. 3 is a vertical which the following is a oal from a suitable bin during bin 2 and P1P through'the'plpe or cylinder 10 is a shaft whereby various novel advantages 7 are gamed. P

ing myinventionzFigure 1 is a top view of a portion of a furnace and my improved =pulver1zed coal feeding apparatus. Fig. 2

section, on line 33 of Fig. 2. Fig.4 is a detail in section, showing the means for automatically regulating the air pressure within the fuel supply pipe.

Referring to the drawings, 2 designates a closedabin adapted to contain the pulverized coal to be fed to the burners and having a portion of its top wall raised to form a horizontally extending channel 4, as shown.

Adjacent to the bin 2 is a fan or blower 5;

and connected to the; outlet of the fan 5 is one end of the main fuel supply pipe 6. The other;end of the pipe "fi'communicates with the upper portion of the bin 2 and dis charges downwardly into one end portion of the channel therein. Leading upwardly from the other end portion of the channel 4 is a. pipe 7 which extends to the fan'5 and is connected to'tlie inlet thereof. The pipes 6 and 7 and the walls of the bin 2'and the casing of the fan 5 form an endless passageway-through which air may} be caused to circulate,-in the direction of the arrows in Fig 2, by the operation ofthe fan 5. ,The operating shaft 8 of the fan 5 is provided with a pulley 9 by means of which the fan 5 may be actuated at any desired speed by any suitable power. I

The. 'owdered coal fed from the bin 2 into the pipe 7 or circulating passageway by the mechanism which I shall now describe. The lower portion, of the bin 2 is made taperi g, and opens into one*end of a cylinder orffpipe 10. The other end of the pipe 10 is connected to the pipe 7 by a short 9 vertical pipe 11,,as shown, the pipes 10 and 11 forming a passageway which connects thee, 7. Extending centrally 12 carrying-a screw conveyer 13, bymeans of. which the powdered coal is. advanced from the bottom of the bin 2 through the pipe 10 and discharged through the pipe 11 into the pipe 7. The sh'aft 12 is journaled in .the end walls of the cylinder or pipe 10; and one end of the shaft 12 extends outwardly and is provided with a pulley 14, hich may be drivenby any suitable power at any desired speed to actuate tlie'conveyer 13, the speed of 'which determines the quantity of coalfed to the pipe 7. Y

The pipe 6 extends adjacent to a ;furnace 'ing through the tuated to feed the powdered coal from the bin 2 to the pipe 7, and the fan 5 is driven V to circulate the air through the pipes 6 and 7, air and powdered coal are driven through the pipe 6 to the burners 16 by the operation of the fan 5, the air pressure'in the pipe 6 being determined by the speed of the fan '5; and the air and coal are discharged from the open burners 16 and into the furnace 15. to feed the fire therein. The coal carried by the air within the pipe 6 in excess of that fed to the open burners 16 is returnedv through the pipe 6 to the bin 2 which acts as a collector as the current of air circulatpipes 6 and 7 passes through the bin 2. Y

As the air and coal are discharged from the burners 16 it becomes necessary to admit additional air to the circulating passageway backof the fan 5, and for this purpose 1 provide the following: The pipe 7 is provided witha valve 19 comprising a cylindrical casing 20 and a valve head 21 slidablewithin the casing. The lower portion of the casing 20 opens into the pipe 7 and the upper portion of the casing 20 hasslots or openings 22 therein adapted to admit outside air to the casing 20 and pipe? when the valve body 21 is raised above the bottom of the openings 22. The valve head 21 is connected by a link 23 to an arm 24 which is pivoted at 25 on a suitable'support 26; and the arm 24 is connected by a link 27 to one arm 28 of a lever 29 which is fulcrumed, at 30, on a suitable support 31. The other arm 32 of the lever 29 is provided with a set of separable and removable weights 33 and is connected by a link 3-1,to the upper end of'a piston 35 which is slidablein a cylinder 36. The cylinder 36 is secured on the pipe 6 and opens the pressure'produced by the fan 5 within thcpi-pe 6 is raised to the said predetermined point; whereupon the said pressure acts against the piston 35 and raises the weighted arm of the lever 29 and closes the valve 19. It will thus be seen that the pressure within the supply pipe 6 is automatically maintained at a given point by the pressure itself. It will also be seen that the point at which the pressure is automatically maintained maybe varied by changing the weights 33 and by changing the speed of the fan 5,01 both.

The powdered'coal is fed to the bin 2 through a vertical pipe 38, the lower end of which discharges into the bin 2 away from the channel 1 therein and below the open end of the circulating pipe 7 leading from the bin, to prevent the coal entering the bin 2 through the pipe 38 from being carried from into the same exposing the lower end of the piston 35 to the pressure within the circulating pipe 6. The arm 32 of the lever 29 carrying the weights 33, is held up against a stop 37 by the air pressure within the pipe 6 acting against the bottom of the piston 35; and, in this position of the, parts, the valve 19 is closed. Now, when the air pressure within the fuel supply pipe 6 falls be low a predetermined point, controlled by the weights 33 and the speed of the fan 5, the piston 35 permits the weights 33 to lower the arm. 32 of thelever 29, thereby raising the arm 28 of the lever 29 and raising the arm 24 and valve head 21 to admit air to the pipe 7 through the openings 22 untilthe bin by the air passing out through the pipe 7. The upper end of the feed pipe 38 communicates with a horizontal pipe or cylinder 39 having a feed screw or conveyer -10 therein which is operative to feed coal through the pipe 39 to the pipe 38, and which, with the coal being fed thereby, serves as a seal to prevent air from entering the bin 2 through the feed pipe 38, during the operation of the apparatus.

I claim:

1. In a pulverized coal feeder, the combination of a closed coal bin, pipes connected to said bin and forming therewith a closed, endless circulating passageway, means to circulate air through said passageway, means to supply one of said pipes with coal from said bin without permitting air to pass from the bin with the coal, and a discharge pipe leading from one of said pipes.

2. In a pulverized coal feeder, thecombination of a coal'bin, a closed circulating pipe communicating with said bin and adapted to receive coal therefrom, means to circulate air through said pipe, and a 'discharge pipe leading from the circulating 3. In a pulverized coal feeder, the combination of a coal bin, a closed circulating pipe, means operative to supply said pipe 'withcoal from said bin, means to clrculate air through said pipe, and a discharge pipe leading from-the circulating pipe.

4. In a pulverized 'coal feeder, the com bination of a closed coal bin,a circulating pipe discharging into and leading from the upper portion .of said 'bin, means to dis charge pulverized coal from the lower portion of said bin and into said pipe, means to circulate air through said pipe, and a discharge pipe leading from the circulatin 5. In a pulverized coal feeder, the comupper portion of said bin, means to supply pulverized coal to the bin, means .to discharge pulverizedcoal from the lower portion of said bin and intosaid pipe, means to circulate air through said pipe, and'a discharge pipe leading from the circulating pipe.

6. In a pulverized coal feeder, the com bination of a closed coal bin, a circulating pipe discharging into and leading from the upper portion of said bin, a supply pipe communicating with the bin at a point below the point where the circulating pipe leads from the bin, means to discharge pulverized coal' from the lower portion of said bin and I into said pipe, means to circulateair through said pipe, and a discharge pipe leading from the circulating pipe. 7. In a pulverized coal .feeder, the combination of walls forming a closed, endless circulating passageway; means to circulate air through said passageway, a discharge pipeleading from said passageway, and

meansto feed pulverized coal to said passageway, the last named means including walls forming a supply passageway communicating with 'the circulating passageway,

and a conveyer within the supply passagef way and operative to advance coal therethrough'.

8. In a pulverized coal feeder, the combination of walls forming a closed, endless circulating passageway, means to circulate air through said passageway, a discharge pipe leading from said passageway, and means to feed pulverized coal to said passagewa'y, the last named means including walls forming a supply passageway communicating with the circulating passageway,

I and a screw conveyer within the supply passageway and operative to advance coal therethrough. 9."In a pulverized coal feeder, the com- I bination of a closed coalbin, a circulating fan, a pipe connecting the upper portion of said bin and the inlet of said fan, a pipe connecting the upper portion of said bin and the outlet of sai'dfan, said fan beingoperative to circulate air through said pipes, a discharge *pipe named pipe, and means to supply said-pipe with coal from said bin.

10. In a pulverized coal feeder, the combination of; a closed coal bin, a circulating fan, a pipe connecting the upper portion of outlet oi sai fan, said fan being operative to circulate airthrough said pipes, walls forming a supply, passageway connecting the lower portionof said bin and one of said pipes, a conveyer within said supply passageway and operative to advance coal therethrough, and a discharge pipe leading from the second named pipe.

leading from the second said bin and the inlet of said fan, a pipe con- I nectingthe u per portion of said bin and the 11. In a pulverized coal feeder, the combination of a closed coal bin, means to sup ply pulverized coal to the bin, acirculating fan, a pipe connecting the'upper. portion of pipe connecting the upper portion of saidbin and the outlet of said fan, said fan being operative to circulate air through said pipes, walls forming a supply passageway connecting the lower portion of said bin and one of said pipes, a conveyer within said supply passageway and operative to advance coal therethrough, and a discharge pipe leading from the second named pipe.

13. In apulverized coal feeder, the com: bination of walls forming an endless lcirculating passageway, means to circulate air through said passageway, a discharge pipe leading from said passageway, means 'to feed pulverized coal to said passageway,

and means controlled by the air pressure within said passageway to automatically' supply air thereto.

14; In a pulverized coal feeder, the combination of a feed pipe, means to blow air means to feed pulverized through said pipe, coal to said pipe, and means controlled by the air pressurewithin said pipe to auto- I matically regulate the air pressure therein.

15. In a pulverized coal feeder, the combination of a coal bin, a circulating pipev communicating with the bin and adapted to receive coal therefrom, means to circulate 110 air through said pipe, a discharge pipe lead-.

ing from the circulating pipe, andmeans controlled by the air-pressure within said pipe to automatically regulate the air pres sure therein. 16 In a pulverized coal bination of a coal bin, a' circulating pipe, means to supply said pipe with coal from said bin, means to circulate air through said pipe, means controlled by the air pressure within said pipe to automatically supply air thereto, and a discharge pipe leading from the circulating pipe.

feeder, the com-.

17.-In a pulverized coal feeder, the combination of a closed coal bin, a circulating pipe discharging into and leading from the upper portion of said bin, means to discharge pulverized coal from the lower portion of said bin and into said pipe, means to circulate air through said pipe, means controlled by the air pressure within said pipe to automatically supply air thereto,

and a discharge pipe leading from the circu latlng pipe;

18. In a pulverized ,coal feeder, the combination of a closed coal bin, a circulating pipe discharging into and leading from the upper portion of said bin, means to supply pulverizedcoal to the bin, means to discharge pulverized coal from the lower portion of 'said bin and into said pipe, means to circulate'air through said pipe, means controlled by'the air pressure within said pipe to automatically supply air thereto, and a discharge pipe leadingfrom the circulating 19. In a pulverized coal feeder, the combination of walls forming an endless circulating passageway, means to circulate air through said passageway, a discharge pipe leading from said pasasgeway, means to feed'pulveriz'ed coal to said passageway, a valve adapted to be operated to admit outside air to said passageway, and means controlled by the air pressure within said passageway for opening and'closing said valve.

20. In a'pulverized coal feeder, the combination of walls forming an endless circulating passageway, means to circulate air through said passageway, a discharge pipe leading from said pasasgeway, means tofeed pulverized coal to said passageway, a-

cylinder communicating with said passage- 'way, a piston within said cylinder and I adapted to be actuated by the air pressure within the passageway, and means operated I by said piston to open and close communica- "tion between said passageway and the outside air. a

21. In a pulverized coal feeder, the combination of walls forming an endless circulating passageway, means to circulate air through said passageway, a discharge pipe leading from said passageway, means to feed pulverized coal to said passageway, a cylinder communicating with said passageway, a piston within said cylinder and adapted to be actuated by the air pressure Within the passageway a valve adapted to 1 be operated to admit outside air to said pass'ageway, and means operated by said piston for opening and closing said valve.

22. In a pulverized coal feeder, the combination of walls forming an endless circulating passageway, means to circulate air through saidpassageway, a discharge pipe leading from said passageway, means to feed pulverized coal-to said passageway, a;

cylinder communicating with said passageway, a piston within said cylinder and adapted to be actuated by the air pressure within the passageway, a weighted lever connected to and operated by said piston,

to advance coal therethrough, a -cylinder communicating with said passageway, a piston within said cylinder and adapted to be actuated bythe air pressure within the passageway, a valve adapted to be operated to admit outside air to said passageway, and means operated by said piston for opening and closing said valve. i

24. In a pulverized coal feeder, the combination of walls forming an endless circulating passageway, means to circulate air through said passageway, means to feed pulverized coal to said passageway, a plurality of valved discharge pipes leading from said passageway, and means controlled by the air pressure within said passageway to automatically supply air thereto.

In testimony whereof Iaflix my signature hereto.

LA RUE B. CHEVALIER.

within the supply passageway and operative 

